The present invention relates to photonics chips and, more specifically, to grating couplers and methods of fabricating grating couplers.
Photonic integrated circuits are devices on which optical and electronic components are integrated. Grating couplers are commonly used to couple light from an optical fiber into an on-chip waveguide, which is considerably smaller than the optical fiber. The grating coupler may be formed by notching the waveguide. Light that diffracts from the grating coupler will constructively interfere at a given scattering angle that is directed toward the optical fiber. The scattering angle of the grating coupler may be determined by the period of the grooves in waveguide.
Improved grating couplers and methods of fabricating grating couplers are needed.